Evaporator



June 12, 1934.

A. LENNING 1,962,512

EVAPORA'IOR Filed May 22. 1929 2 Sheets-Sheet l 30 3a U i j A. LENNING June 12, 1934.

EVAPORATOR f Filed ma 22. 1929.

' 2 Sheets-Sheet 2 INVEN M BY r type.

Patented June 12, 1934 UNITED STATES EVAPORA'IOE Alvar Lenning, Jackson Heights, N. Y., assignor to Electrolux Serve! Corporation, New York, I N. Y., a corporation of Delaware Application May 22, 1929, Serial No. 364,971

27 Claims. (01. 62-126) My invention relates to refrigerating systems and more particularly to evaporators for refrigcrating systems. Still more particularly my in vention relates to evaporators for use in systems in which the pressure is equalized by means of a gas which is inert with respect to the refrigerant.

In refrigerating systems where there is no drop in pressure between the point of liquid supply to the evaporator and the evaporator, division of liquid into a plurality of streams presents a problem. Subdivision into a plurality of streams facilitates construction of an evaporator in whole or in part of tubing. .When there is only one path of liquid flow through the evaporator in one direction as in gravity-evaporators, it has been found necessary to providerelatively elaborate .means for obtaining good heat transfer between the space to be cooled and the evaporator.

My present invention provides means for separating liquid refrigerant into several streams without having a drop in total pressure, thereby facilitating the construction of an evaporator, particularly for systems of the equalized pressure To do this I cause the liquid refrigerant to drop onto a knife edge separator which divides the drops, part of the liquid passing to one side and part to the other of the knife edge separator.

Another object of my invention is to provide a novel form of evaporator particularly suited for equalized pressure systems.

The nature of the invention will become apparent from thefollowing description taken in connection with the accompanying drawings forming part of this specification and of which:

Fig. 1 is a top view of an evaporator embodying the invention;

Fig. 2 is a sectional view taken on line 2-2 of isv Fig. 3 is a view taken on the line 3-3 of Fig. 2;

Fig. 4 is a sectional view of part of the evaporator taken on line 4-4 ofFig. 1;

Fig. 5 is a sectional view of part of the evap-- oratortaken on line 5--5 of Fig. 2;

Fig. 6 is a sectional view of an evaporator showing a second embodiment of the invention, which view is taken on line 6-6 of Fig. 7; and

Fig. 7 is a sectional view taken on line 7-7 of' Fig. 6. i

The particular evaporator shown in Fig. 1 is designed for a system of the type shown in U. S. Patent 1,609,334 granted December 7,1926, to von Platen and Munters. Such system is of equal pressure throughout by virtue of an auxiliary .agent such as hydrogen into which the cooling agent or refrigerant such as ammonia evaporates. I

The evaporator is supplied with a cooling agent or refrigerant such as ammonia through conduit 10 which extends within conduit 11. Conduit 11 supplies an auxiliary agent or inert gas such as hydrogen to the evaporator. Conduit 11 is connected to a horizontal hollow cross connection 12 preferably made of rectangular or square tubing..

the upperends of forwardly posited loops serve for supporting ice trays 18 in chamber 15. The ice trays have upper flanges for supporting them on the horizontal conduit portions. The ice trays can be removed from chamber by merely pulling them forward. Conduits 14 are preferably of square or rectangular form to give good supporting surfaces for the trays and to provide adequate liquid surface inside the same.

The lower ends of conduits 14 are connected to a cross-connection 19 positioned below connection 12. A conduit 20 conducts the gaseous mixture formed in the evaporator away therefrom and toward the absorber.

Conduit 10, which conducts liquid refrigerant from the condenser of the system to the evaporator projects within connection 12. ,The end 21 of conduit 10 is formed to make drops of the liquid passing therethrough, the end being bent downwardly and tapered in a snout-like formation.

Immediately below projection 21 is a member 22 which is set into connection 12. Member 22 extends upwardly and has a knife edge top.

Drops of liquid falling down from projection 21 onto the knife edge of member 22 are split,

part of the drop passing to each side of the knife which are slipped over the conduits and spotwelded thereto and a back plate 31. When close together the plate 31 and flanged members 30 give a closed chamber.

wardly and serve to aid the heat transfer. Sufficient space is left above the top horizontal conduit portions under the flanged members to permit hanging'the upper tray thereon.

With an arrangement as above described comprising a single knife edge it would. be necessary I A door may be placed over the front opening. The flanges project out- .stitute a plurality of knife edges.

to have the evaporator level so that the dropping point is vertically over the knife edge. To avoid the necessity of leveling I propose the arrangement shown in Fig. 6 and Fig. '7 wherein a crosspiece 23 is fitted into the connection 12. This cross-piece may be made of a block of metal cut alternately from one side downwardly to the other to form inclines running to opposite sides. Cuts 24 run from the top downwardly to the right as shown and cuts 25 run from the top downwardly to the left as shown. The ridges 26 left between the cuts are very narrow and con- The cuts are preferably of less width than the diameter of a normal drop. Thus there is formed a number of \knife edges parallel to each other and so arranged that the drops will be divided even though the evaporator is out of level position by a considerable amount. The parts of the drops run down the inclines to opposite sides.

While I have shown two embodiments of the invention, it will be understood that the invention may be embodied in a great number of forms of apparatus.

Having thus described my invention, what I claim is:

1. An evaporator comprising members forming a plurality of paths of liquid flow, a liquid supply conduit adapted to drop liquid therefrom for supplying liquid to said members and a liquid divider element in said means in the path of liquid dropping from said supply conduit.

2. An evaporator comprising members forming a plurality of paths of liquid flow, a liquid supply conduit adapted to drop liquid therefrom for Supplying liquid to said members and a liquid divider element having a knife edge in said means in the path of liquid dropping from said supply conduit.

3. An evaporator comprising a pair of vertically extending conduits, a hollow connection connecting the upper parts of said conduits, a liquid supply conduit projecting into said hollow connection and means in said hollow connection providing a knife edge vertically below the projection of the liquid supply conduit into the hollow connection.

a. An evaporator comprising a pair of vertically extending conduits, a hollow connection connecting the upper parts of said conduits, a liquid supply conduit proiecting into said hollow connection adapted to drop liquid thereinto and a liquid divider in said hollow connection below the projection of the liquid supply conduit thereinto and in the path of liquid dropping from the supply conduit for separating the dropping liquid into separate streams.

5. An evaporator comprising a pair of vertical.- ly extending conduits, a hollow connection connecting the upper parts of said conduits, a liquid supply conduit projecting into said hollow connection and a liquid divider in said hollow connection below the projection of the liquid supply conduit thereinto comprising a cross-piece having a zig-zag upper edge and inclined surfaces ex-- tending downwardly to each side of the crosspiece.

6. An evaporator-comprising a pair of vertically extending conduits, a hollow connection connecting the upper parts of said conduits, a liquid supply conduit projecting into said hollow connection, means in said hollow connection providing a knife edge vertically below the projection of the liquid supply conduit thereinto and means to supply an auxiliary gas to the evaporator.

'7. An evaporatorcomprising a pair of vertically extending conduits, a hollow connection connecting the upper parts of said. conduits, a liquid supply conduit projecting into said hollow connection, a liquid divider in said hollow connection vertically below the projection of the liquid supply conduit thereinto for separating liquid dropping from said supply conduit into separate streams and means to supply an auxiliary gas to the evaporator.

8. An evaporator comprising a pair of vertically disposed similar zig-zag conduits having horizontal portions serving to support ice trays, a hollow connection connecting the upper parts of said conduits, a liquid supply conduit projecting into said hollow connection, a liquid divider in said hollow connection below the projection of the liquid supply conduit thereinto and a connection between the lower ends of the zig zag conduits.

9. An evaporator comprising a pair of vertically disposed similar zig-zag conduits having horizontal portions serving to support ice trays, a hollow connection connecting the upper parts of said conduits, a liquid supply conduit projecting into said hollow connection, a liquid divider in said hollow connection below the projection of the liquid supply conduit thereinto, a connection between the lower ends of the zig-zag conduits and flanged members encasing said zig-zag conduits.

10. An evaporator comprising a pair of vertically disposed similar zig-zag conduits having horizontal portions serving to support ice trays,

a hollow connection connecting the upper parts l the evaporator.

11. An evaporator comprising an upper crossconnection, a lower cross-connection, a pair of spaced zig-zag conduits connected at top and bottom to said cross-connections, said zig-zag conduits having horizontal portions and ice trays having lateral flanges, said trays supported by said flanges on said horizontal portions.

12. An evaporator comprising an upper crossconnection, a lower cross-connection, a pair of spaced zig-zag conduits of rectangular cross-section connected at top and bottom to said crossconnections, said zig-zag conduits having hori zontal portions and ice trays having lateral flanges, said trays supported by said flanges on said horizontal portions.

13. An evaporator comprising members forming a plurality of paths of flow and means for subdividing a stream of liquid to flow in said paths without change of total pressure comprising an edge directed toward the stream. 0

14. An evaporator comprising an upper crossconnection, a lower cross-connection, a pair of zigzag conduits connected at top and bottom to said cross-connections, said zigzag conduits having horizontal portions, ice trays supported on said horizontal portions, a liquid supply conduit projecting into said upper cross-connection, and

tions connecting the horizontal portions alter-- nately at the front and back of the evaporator and providing receiving spaces accessible from the front' for receiving supporting parts of ice trays and horizontal portions .'of the conduits at the upper ends of forwardly-posited curved portions serving to support ice trays h'ung thereon between the zigzag conduits.

16. An evaporator comprising an upper cross,-

connection, a lower cross-connection, a pair of laterally disposed zigzag conduitsconnected at the top' and bottom to said cross-connections, said zigzag conduits having parallel-horizontal portions and curved portions connecting the horizontal portions alternately at the front and back of the evaporator, a box-likew heat transmitting structure enclosing said zigzag conduits an dhaving an opening in the front thereof, and ice trays provided with upper longitudinally extending flanges, said flanges engaging the horizontal portions of said zigzag conduits to support the trays thereon and within said box-like structure;

17. An evaporator comprising an upper crossconnection, a lower cross-connection, a pair of laterally disposed zigzag co'nd'uits connected at the top and bottom to said cross-connections, said zigzag conduits having horizontal portions, 2.

box-likestructure surrounding said zigzag conduits, said structure comprising a series of rectangular bands with out-turned flanges formed thereon, and ice trays supported on said horizontal portions and within said structure.

18. An evaporator comprising an upper cross connection, a lower cross-connection, a pair of laterally disposed zigzag conduits connected at the top and bottom to said cross-connections, said zigzag conduits having parallel horizontal portions, a box-like structure surrounding said zigzagconduits, said structure comprising a series of rectangular-bands with out-turned flanges formed thereon, ice trays pro'vlded'with upper longitudinally extending flanges, said flanges engaging the horizontal portions of said zigzag conduits to, support the trays thereon and within said box-like structure, a liquid supplylconduit communicating with-said upper crossconnection and means for dividing liquid supplied through saidliquid supply conduit.

19,, An evaporatorcomprising a pair of verti-.- cally extending conduits, a hollow connection connecting thev upper parts of said conduits, a liquid supply conduit projecting into said hollow connection for dropping liquid thereinto, *a liquid divider in said hollow connection below the projection of the liquid supply conduit thereinto and in the path of liquid dropping from the supply conduit for separating the dropping liquid into separate streams, a lower hollow connection connecting the'lower ends, of said vertically extending conduits and a conduitrfor convey Va.- por from said lower hollow connection.

20'. An evaporator comprising a pair of vertically extending conduits-a. hollow connection connecting the upper-parts of said conduits, a liquid supplyconduit projecting into saidhollow connection ,for dropping liquid thereinto, a. liduid'divider in said hollow connection below the projection of the liquid supply conduit thereinto and in the path of liquid dropping from the supply conduit for separating the dropping liquid into separate streams, a lower hollow connection connecting the lower ends of said vertically extending conduits, means for supplying an auxiliary gas to said evaporator and a conduit for conveying vapor from said lower hollow connec tion 21. An evaporator comprising horizontally spaced conduits having substantially parallel horizontal portions connected by conduit bends, and substantially opposite horizontal portions of said spaced conduits. beingarranged to support lateral flanges of an 'ice tray.

22. An evaporator comprising a sheet metal casing, -a refrigerant conduit secured in good thermal contact with an inner surface of each side wall of saidcasing, said spaced conduits being provided with substantially horizontal parallel portions for receiving and supporting the lateral flanges of ice trays, I I 23. An evaporator comprising a sheet metal casing, a refrigerant conduit secured in good thermal contact with an .inner surface of each side wall of said casing,.said spaced conduits being provided with substantially horizontal par-- allel portions for receiving and supporting the lateralfianges oi ice trays, said conduits being interconnected at their extremities.

24. An evaporator comprising a sheet metal casing, a refrigerant conduit secured in good thermal contact with an inner surface of each side wall of said casing, said spaced conduits being provided with substantially horizontal par allelportions forreceivingland supporting the lateral flanges of ice' trays, said casing being formed of a plurality/of sections having heatradiatingfins. 25.- An evaporator comprising a conduit having horizontally. spaced parts comprising substantially parallel horizontal portions connected by conduit bends, and substantially opposite horizontal portions: pi -said spaced parts being arranged to support lateral flanges of an ice tray. 26. An evaporator comprising a heat conduct ing casing forming an enclosure open at the front for insertion of ice trays, conduits in heat exchange relation with each side of the casing haying substantially horizontal portions and con nected for continuous downward flow of'liquid refrigerant therethrough and having no portions thereof at the front of the enclosure, said condu'its being constructed and arranged for flow of inert gas therethrough; and. separate conduits for supplying liquid refrigerant and inert gas to the aforementioned conduits. v

27. An evaporator comprising a housing-strum ture enclosing an ice tray chamber, and a com duit in heat exchange relation with said housing structure, said conduit being of such large cross-sectional area as to carry a volume of liquid refrigerant-necessary for evaporation and aconsiderably greater volume of inert gas, said- 1 

